New dielectric material system of Nd(Mg_(1/2)Ti_(1/2))O_3-CaTiO_3 at microwave frequency

摘要

The microwave dielectric properties of (1- x)CaTiO_3-xNd(Mg_(1/2)Ti_(1/2))O_3 (0.1 ≤ x ≤ 1.0) ceramics prepared by the conventional solid state method have been investigated. The system forms a solid solution throughout the entire compositional range. The dielectric constant decreases from 152 to 27 as x varies from 0.1 to 1.0. In the (1 - x)CaTiO_3-xNd(Mg_(1/2)Ti_(1/2))O_3 system, the microwave dielectric properties can be effectively controlled by varying the x value. At 1400℃, 0.1CaTiO_3-0.9Nd(Mg_(1/2)Ti_(1/2))O_3 has a dielectric constant (ε_r) of 42, a Q x f value of 35000 GHz and a temperature coefficient of resonant frequency (τ_f) of -10 ppm/℃. As the content of Nd(Mg_(1/2)Ti_(1/2))O_3 increases, the highest Q xf value of 43000 GHz for x = 0.9 is achieved at the sintering temperature 1500℃.